In recent years, there has been rapid progress in increasing performance of and functionalities in a high frequency semiconductor switch that is used in reception and transmission circuits for communication. In addition, there has been a strong demand for low cost, miniaturization, high integration, and low power consumption. To meet such demands, a High Electron Mobility transistor (HEMT) has been used as a substitute for compound semiconductor devices, and multiple high frequency semiconductor switches employing a Silicon On Insulator (SOI)-type MOS transistor in which the parasitic capacitance is smaller than a Metal Oxide Semiconductor (MOS) transistor formed on a silicon substrate and which is able to lower the power loss, are being developed.
For a high frequency semiconductor switch having a switch circuit and a control circuit mounted on the same semiconductor substrate, there is a problem that a high frequency signal leaks out to the control circuit to adversely affect the operation of the switch circuit. For a high frequency semiconductor switch that uses a digital modulation method, the design requirement on the switch is more stringent than with the conventional high frequency semiconductor switches, and includes low distortion and superior linearity.